Commit 7561e8ca authored by David Howells's avatar David Howells Committed by Linus Torvalds

NOMMU: Revert 'nommu: get_user_pages(): pin last page on non-page-aligned start'

Revert the following patch:

	commit c08c6e1f
	Author: Steven J. Magnani <steve@digidescorp.com>
	Date:   Fri Mar 5 13:42:24 2010 -0800

	nommu: get_user_pages(): pin last page on non-page-aligned start

As it assumes that the mappings begin at the start of pages - something that
isn't necessarily true on NOMMU systems.  On NOMMU systems, it is possible for
a mapping to only occupy part of the page, and not necessarily touch either end
of it; in fact it's also possible for multiple non-overlapping mappings to
coexist on one page (consider direct mappings of ROMFS files, for example).
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Acked-by: default avatarSteven J. Magnani <steve@digidescorp.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 39f1cd63
......@@ -146,7 +146,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
(VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
for (i = 0; i < nr_pages; i++) {
vma = find_extend_vma(mm, start);
vma = find_vma(mm, start);
if (!vma)
goto finish_or_fault;
......@@ -764,7 +764,7 @@ EXPORT_SYMBOL(find_vma);
*/
struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr)
{
return find_vma(mm, addr & PAGE_MASK);
return find_vma(mm, addr);
}
/*
......
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